I went to rookmore after reading a note saying there was metal scrap. I demolished the place. There was nothing left. I vandalised every tower, wooden barrel, table, anything. I am still using that scrap in late game. Will never forget rookmore.

Correction: the metal scrap (from the place with the wolf and the archer) is usually on the archer, rather than in the debris (and maybe the video mentioned this?)

Rookmore is indeed a great place to get scrap, and I guess this guide is good for people who managed to overlook the Blacksmith's journal suggestion to go there for metal scrap.

But for people just starting, it's important to get some metal scrap together for crafting in preparation for visiting Rookmore (you'll want a grapple, and melee fighters will want a scrappy weapon, and some armor). And, for that...

There's a place in Longkeep with 2 metal scrap which respawns (the enshrouded ruined building behind the two targets with collectable arrows, right by the entrance to that little ruin, which is by the well). The location where you find the blacksmith has things which can be blown up or smashed for metal scrap (if you're desperate and patient, you can even smash the metal kettles for some scrap, but that's tedious), and the place with the wolf and the single archer on the way to Rookmore has some scrap when you blow up the explosive barrels.

Thanks for sharing this, it was very helpful.

For anyone interested, I have since figured out that for 5 stone, I can build an altar there for fast travel to and from.

Isnt Rookmore marked in the Quest "Forge Weaponry or Armor" as place to get metal scraps from?
Not really a tip when the game tells you that already.

Thanks for sharing!